Enhanced chip select signal training

Abstract

In some aspects, a system may include a host device and a memory device. The host may transmit a clock signal having a first frequency to the memory and, for a chip select training operation, transmit a chip select signal with a pattern of high pulses and low pulses. The host may initiate, for a sampling window, a chip select training operation with the memory using the clock signal and chip select signal, the sampling window including a quantity of pulses of the signal. The memory may perform the chip select training operation for the sampling window using the clock signal and chip select signal from the host. The memory may provide, via a first data in or out (DQ) pin, an indication of a result for the high pulses, and via a second DQ pin, an indication of a result for the low pulses. Numerous other aspects are described.

What is claimed is: 
     
         1 . A system, comprising:
 a host device, and a memory device, the system configured to:
 transmit, by the host device, a clock signal having a first frequency to the memory device; 
 transmit, by the host device and for a chip select training operation, a chip select signal to the memory device, the chip select signal having a pattern including high pulses and low pulses; 
 initiate, by the host device and for a sampling window, a chip select training operation with the memory device using the clock signal and the chip select signal,
 wherein the sampling window includes a quantity of pulses of the chip select signal; 
 
 perform, by the memory device and for the sampling window, the chip select training operation using the clock signal and the chip select signal received from the host device; 
 provide, by the memory device via a first data in or out (DQ) pin, an indication of a first result of the chip select training operation for the high pulses of the chip select signal; and 
 provide, by the memory device via a second DQ pin, an indication of a second result of the chip select training operation for the low pulses of the chip select signal, 
 wherein the indication of the second result is not provided via the first DQ pin and the indication of the first result is not provided via the second DQ pin. 
   
     
     
         2 . The system of  claim 1 , wherein the host device, to initiate the chip select training operation, is configured to alternate transmission of high pulses and low pulses of the chip select signal on rising edges of the clock signal. 
     
     
         3 . The system of  claim 2 , wherein the host device, to alternate transmission of high pulses and low pulses, is configured to:
 transmit the high pulses of the chip select signal on even rising edges of the clock signal, and   transmit the low pulses of the chip select signal on odd rising edges of the clock signal.   
     
     
         4 . The system of  claim 1 , wherein the host device is further configured to determine the quantity of pulses of the chip select signal included in the sampling window. 
     
     
         5 . The system of  claim 4 , wherein the host device, to determine the quantity of pulses, is configured to transmit to the memory device an indication of the quantity of pulses of the chip select signal included in the sampling window. 
     
     
         6 . The system of  claim 4 , wherein the host device, to determine the quantity of pulses, is configured to determine the quantity of pulses using chip select signals associated with one or more chip select training operations performed prior to the chip select training operation. 
     
     
         7 . The system of  claim 1 , wherein the host device, to initiate the chip select training operation, is configured to:
 transmit an indication to the memory device that the chip select training operation is enabled,   transmit the chip select signal for the quantity of pulses of the chip select signal, and   refrain from transmitting the chip select signal for the chip select training operation after the quantity of pulses have been transmitted.   
     
     
         8 . The system of  claim 1 , wherein the memory device, in providing the indication of the first result, is configured to:
 provide, via the first DQ pin, an indication of a failure associated with a high pulse of the chip select signal, wherein the indication of the failure is persistently indicated via the first DQ pin for at least the sampling window.   
     
     
         9 . The system of  claim 1 , wherein the memory device, in providing the indication of the second result, is configured to:
 provide, via the second DQ pin, an indication of a failure associated with a low pulse of the chip select signal, wherein the indication of the failure is persistently indicated via the second DQ pin for at least the sampling window.   
     
     
         10 . The system of  claim 1 , wherein the host device is further configured to:
 reduce, prior to initiating the chip select training operation, the first frequency of the clock signal to a second frequency, and   transmit, in association with reducing the first frequency, an indication to the memory device that the chip select training operation is enabled.   
     
     
         11 . The system of  claim 1 , wherein the host device is further configured to:
 reduce, after the chip select training operation, the first frequency of the clock signal to a second frequency, and   transmit, in association with reducing the first frequency, an indication to the memory device that the chip select training operation is disabled.   
     
     
         12 . The system of  claim 1 , wherein the memory device, to perform the chip select training operation, is configured to sample, for the sampling window, the chip select signal on edges of the clock signal. 
     
     
         13 . The system of  claim 1 , wherein the memory device is configured to alternate between sampling high pulses and low pulses of the chip select signal on the edges of the clock signal. 
     
     
         14 . The system of  claim 13 , wherein the memory device is configured to sample the high pulses of the chip select signal on even rising edges and the low pulses of the chip select signal on odd rising edges of the clock signal. 
     
     
         15 . The system of  claim 1 , wherein the host device is configured to transmit a chip select signal having a clock-like pattern to the memory device during the chip select training operation. 
     
     
         16 . The system of  claim 1 , wherein the host device is configured to transmit a chip select signal with a defined pulse pattern to the memory device during the chip select training operation. 
     
     
         17 . The system of  claim 1 , wherein the host device is configured to perform one or more additional chip select training operations using different chip select signal toggle patterns, different pulse widths, or different delays of the chip select signal. 
     
     
         18 . A method performed by a system including a host device and a memory device, comprising:
 transmitting, by the host device, a clock signal having a first frequency to the memory device;   transmitting, by the host device and for a chip select training operation, a chip select signal to the memory device, the chip select signal having a pattern including high pulses and low pulses;   initiating, by the host device and for a sampling window, a chip select training operation with the memory device using the clock signal and the chip select signal, the sampling window including a quantity of pulses of the chip select signal;   performing, by the memory device and for the sampling window, the chip select training operation using the clock signal and the chip select signal received from the host device;   providing, by the memory device via a first data in or out (DQ) pin, an indication of a first result of the chip select training operation for the high pulses of the chip select signal; and   providing, by the memory device via a second DQ pin, an indication of a second result of the chip select training operation for the low pulses of the chip select signal, wherein the indication of the second result is not provided via the first DQ pin and the indication of the first result is not provided via the second DQ pin.   
     
     
         19 . The method of  claim 18 , wherein the host device, to initiate the chip select training operation, alternates transmission of high pulses and low pulses of the chip select signal on rising edges of the clock signal. 
     
     
         20 . The method of  claim 19 , wherein the host device transmits the high pulses of the chip select signal on even rising edges of the clock signal, and transmits the low pulses of the chip select signal on odd rising edges of the clock signal. 
     
     
         21 . The method of  claim 18 , further comprising, by the host device, determining the quantity of pulses of the chip select signal included in the sampling window. 
     
     
         22 . The method of  claim 21 , wherein determining the quantity of pulses comprises transmitting, by the host device to the memory device, an indication of the quantity of pulses of the chip select signal included in the sampling window. 
     
     
         23 . The method of  claim 21 , wherein determining the quantity of pulses comprises determining, by the host device, the quantity of pulses using chip select signals associated with one or more chip select training operations performed prior to the chip select training operation. 
     
     
         24 . The method of  claim 18 , further comprising:
 transmitting, by the host device, an indication to the memory device that the chip select training operation is enabled;   transmitting, by the host device, the chip select signal for the quantity of pulses of the chip select signal; and   refraining, by the host device, from transmitting the chip select signal for the chip select training operation after the quantity of pulses have been transmitted.   
     
     
         25 . The method of  claim 18 , further comprising, by the memory device, providing, via the first DQ pin, an indication of a failure associated with a high pulse of the chip select signal, wherein the indication of the failure is persistently indicated via the first DQ pin for at least the sampling window. 
     
     
         26 . The method of  claim 18 , further comprising, by the memory device, providing, via the second DQ pin, an indication of a failure associated with a low pulse of the chip select signal, wherein the indication of the failure is persistently indicated via the second DQ pin for at least the sampling window. 
     
     
         27 . The method of  claim 18 , further comprising, by the host device:
 reducing, prior to initiating the chip select training operation, the first frequency of the clock signal to a second frequency; and   transmitting, in association with reducing the first frequency, an indication to the memory device that the chip select training operation is enabled.   
     
     
         28 . The method of  claim 18 , further comprising, by the host device:
 reducing, after the chip select training operation, the first frequency of the clock signal to a second frequency; and   transmitting, in association with reducing the first frequency, an indication to the memory device that the chip select training operation is disabled.   
     
     
         29 . An apparatus, comprising:
 means for transmitting a clock signal having a first frequency to a memory device;   means for transmitting, for a chip select training operation, a chip select signal to the memory device, the chip select signal having a pattern including high pulses and low pulses;   means for initiating, for a sampling window, a chip select training operation with the memory device using the clock signal and the chip select signal, the sampling window including a quantity of pulses of the chip select signal;   means for causing the memory device to perform, for the sampling window, the chip select training operation using the clock signal and the chip select signal received from the host device;   means for obtaining, from the memory device via a first data in or out (DQ) pin, an indication of a first result of the chip select training operation for the high pulses of the chip select signal; and   means for obtaining, from the memory device via a second DQ pin, an indication of a second result of the chip select training operation for the low pulses of the chip select signal,
 wherein the indication of the second result is not obtained via the first DQ pin and the indication of the first result is not obtained via the second DQ pin. 
   
     
     
         30 . A non-transitory computer-readable medium storing a set of instructions, the set of instructions comprising:
 one or more instructions that, when executed by one or more processors of a system, cause the system to:
 transmit, by the host device, a clock signal having a first frequency to the memory device; 
 transmit, by the host device and for a chip select training operation, a chip select signal to the memory device, the chip select signal having a pattern including high pulses and low pulses; 
 initiate, by the host device and for a sampling window, a chip select training operation with the memory device using the clock signal and the chip select signal, the sampling window including a quantity of pulses of the chip select signal; 
 cause the memory device to perform, for the sampling window, the chip select training operation using the clock signal and the chip select signal received from the host device; 
 obtain, from the memory device via a first data in or out (DQ) pin, an indication of a first result of the chip select training operation for the high pulses of the chip select signal; and 
 obtain, from the memory device via a second DQ pin, an indication of a second result of the chip select training operation for the low pulses of the chip select signal,
 wherein the indication of the second result is not obtained via the first DQ pin and the indication of the first result is not obtained via the second DQ pin.